1. Field of the Invention
The present invention relates to an orthogonal frequency division multiplexing (OFDM) method based on 3-dimensional (3D) signal constellation.
2. Description of the Related Art
In wireless communication technology fields, 2-dimensional (2D) signal constellation is used as a signal mapper in an orthogonal frequency division multiplexing (OFDM) apparatus. A conventional OFDM apparatus of this kind using a 2D signal constellation as a signal mapper is widely used in both wireless communication apparatuses and mobile communication apparatuses, but the structure of the conventional OFDM apparatus has hardly been changed after its design in the early 1980's.
Especially in 1990s, OFDM apparatuses were recommended for and adopted as the technical standard for European digital broadcasting and IEEE 802.11 wireless local area networks (WLANS). Accordingly, a conventional structure of OFDM apparatuses is invulnerable.